After noticing something strange about the wall.
Uchiha Ao didn't act rashly.
The Second, Senju Tobirama, had been a deeply suspicious man. If he'd hidden a place like this in the wall, it either held something valuable or was a trap.
It was meant to keep ordinary people from seeing it—and to ensnare anyone with ulterior motives.
He didn't want to fall into Senju Tobirama's trap.
So he checked several times.
He examined every suspicious detail over and over.
He found two concealed mechanisms. But as time passed, the facilities left behind had stopped working, leaving only a few patterns on the wall.
The first was a concealment genjutsu. Without Chakra to sustain it, only a faint trace remained, and it no longer worked as it had originally.
That was how he'd discovered the hidden room.
The second was an explosive trap. Touching it without using a specific method would set off an explosion inside. The slightest mistake could cost someone a finger or an arm—or kill them on the spot.
But under the Sharingan's scrutiny, he removed the explosive runes and neutralized the trap.
After dealing with the two problems,
Ao opened the place Senju Tobirama had hidden.
It was a small chamber of about sixty square centimeters, with three objects inside.
The first was a notebook two fingers thick, filled with writing. Its pages showed signs of weathering after all these years.
Ao picked it up and flipped through the first and last pages. It was Senju Tobirama's Experimental Diary, recording the jutsu research he'd conducted from the age of ten onward, including summaries of his final project and its findings.
It offered a glimpse into Senju Tobirama's approach to research.
It was an excellent reference, one that could provide plenty of inspiration for future research.
The second item was a Contract Scroll.
Contractee... Death God
Contractor... Ashina Uzumaki
Ao stared at the contents, perplexed. Why was it something like this? Why was an Uzumaki Family Contract Scroll in Senju Tobirama's possession?
Could he have obtained it during the destruction of the Uzumaki Family?
Judging by the contents, this must have been a contract made by one of the Uzumaki Clan's former leaders with a demon god. In exchange for their soul, they'd received a sealing technique.
Though the contract didn't name the technique, Ao recognized it from the hand seals described on the scroll.
It was the Dead Demon Consuming Seal.
He'd seen those hand seals in materials Orochimaru had provided.
Snake-Dragon-Ram-Rabbit-Dog-Rat-Rooster-Horse-Snake!
After forming the seals, the user could summon the Death God and sacrifice their own power to gain its help in devouring an enemy's soul.
After studying the contract closely, Ao found nothing particularly special about it. It described only a simple transaction.
There weren't even any detailed terms.
It merely stated that a soul had been exchanged with a demon god.
Why had Senju Tobirama thought it important enough to keep in a hidden room?
Ao was puzzled.
After thinking it over...
He decided to try looking at it another way, to see if he could uncover its secrets.
Ao sat cross-legged on the floor and swiftly formed the hand seals for a jutsu.
"Spirit Transformation Technique!"
His soul, glowing with a pale blue light, slowly floated upward.
In his spirit form,
he could see many details that were hidden in the physical world.
When he looked at the contract again as a spirit,
he saw that the paper, made of some unknown material, was giving off a dark light.
A thread stretched out toward somewhere in the void.
When Ao followed the thread with his gaze, a terrifying face appeared before him: a masked monster with a blue face and bared fangs.
The creature seemed to sense his gaze. Its face abruptly turned, and it stared straight at Uchiha Ao.
At a single glance, an intense sense of danger welled up inside Ao.
An eerie force of attraction emerged from the void, slowly drawing him toward it.
Something was wrong!
Could that thing follow the thread to him?!
Ao reacted at once, ending the technique and returning to his body.
"Shit! Senju Tobirama... What kind of terrifying thing did you leave behind? I almost had a heart attack!"
"Is this really something a Jonin who's barely made it out of the newbie village can meddle with?"
"That's the Death God?!"
Once Ao's soul returned to his body, he cursed furiously, his face ashen.
Senju Tobirama really was a devious old bastard.
He'd almost been caught!
This contract was like the Uzumaki Mask: it could connect directly to the Death God itself. And it might not be an incarnation—it could be the real thing.
Ao turned the Contract Scroll over. The back was covered in names from the Uzumaki Clan, apparently the names of every person who'd used the technique.
What kind of paper could retain its texture after all these years?
Ao had the persistent feeling that something was watching him. He didn't dare waste another moment. He quickly took out the box Orochimaru had opened earlier, put the Contract Scroll inside, and shut it. Then he used Chakra to make a barrier around it, masking its presence as best he could.
Finally, he sealed it inside a scroll.
Only then did the prickling sensation of being watched begin to fade.
He drew in a sharp breath.
It felt as though he'd picked up something unclean.
Damn the Uzumaki Clan.
He cursed them under his breath. Having something like that set its sights on him was bad luck.
Maybe he should visit the Uzumaki Clan's lands and see if that mask could dispel the bad luck.
He also needed to learn some Sealing Jutsu...
Better safe than sorry.
As he considered this, his gaze fell on the last object in the hidden room.
A specially made Kunai, engraved with a unique rune.
The markings on it looked familiar.
After picking it up and examining it closely, Ao realized it resembled the contract he'd just seen. What was this thing for? Controlling souls?
Wait...
Would Senju Tobirama really leave something so ordinary here?
He asked himself honestly.
If he were Senju Tobirama, he'd never leave a simple, standard-issue Kunai here.
He thought it over.
Then he suddenly sensed movement behind him.
He turned and saw Orochimaru standing in the laboratory doorway.
"Ao-kun, it looks like you've found something remarkable!"
Orochimaru asked, his eyes greedy.
After a period of training, his soul had not weakened from Living Corpse Reincarnation. If anything, it had grown stronger.
He'd keenly sensed the commotion Uchiha Ao had caused in the laboratory.
He'd immediately dropped what he was doing and hurried over.
He'd arrived just in time to see Uchiha Ao examining a strange, specially made Kunai.
"Teacher, this is something the Second left behind. I couldn't figure out what it does, so I was just about to bring it to you."
Ao turned and held out the Kunai to Orochimaru.
Orochimaru discreetly surveyed the laboratory. Compared to when he'd first entered, two useless boxes were gone.
Everything else was untouched.
Yet in the otherwise empty laboratory, the Second's hidden room had been uncovered.
This kid... He really was sharp.
He'd found a place that had been hidden so well.
Orochimaru was impressed. He'd been focused on gathering things and in a hurry. After opening one of the two wooden boxes and finding nothing inside, he'd left the other alone.
He hadn't expected there to be a hidden space behind them.
"This is a specially made Kunai for the Flying Thunder God. It bears the Second's personal mark..."
Orochimaru took the Kunai, gave it a quick look, and explained.
Then, after studying it more closely, he noticed something was off.
"Wait... No... This isn't the Flying Thunder God!"
Orochimaru suddenly pulled out a scroll and unfurled it in his hand, swiftly skimming past the earlier contents until he reached the end.
A symbol almost identical to the one on the Kunai was drawn on the scroll.
"Impure World Reincarnation: Soul Manipulation Technique!"
An unnatural flush spread across Orochimaru's face as he spoke with excitement.
"I can't believe the Second had already worked this out! But he didn't mention it in his research on the Impure World Reincarnation, and this mark is incomplete..."
"What method did he come up with to solve the problem of controlling souls?"
"With this, the Impure World Reincarnation Jutsu would be complete! But why didn't the Second use it in the First Shinobi World War?"
Orochimaru muttered to himself, his confusion gradually giving way to a faint redness in his eyes.
"Second..."
Orochimaru gritted his teeth and spat out the words.
This jutsu could bring the dead back to life with nearly half their former strength. If he summoned the First, even with only half his power, he could have easily ended the First Shinobi World War.
Then his parents wouldn't have died in the war.
Second...
What were you thinking?!
Orochimaru's expression darkened, and a trace of hatred surfaced in his eyes.
For once, the calm expression he'd always maintained faltered.
Before you continue